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Connect the bornier in place of the computer and check the insulation and continuity of the line :
Computer 29 2 Coil
Computer 28 1 Coil
Repair if necessary.
JSA052.0
INJECTION
Fault finding - Interpretation of XR25 bargraphs17
D7F 710
engine -
55 tracks
Turn the engine, switch the ignition on and erase the computer memory using
G0**. Try to start the engine. Switch the ignition on, then deal with the other
faults. Remember to carry out a status and parameter check.AFTER REPAIR
Bargraph 16 LH side illuminated Fiche n° 27 side 1
COMPUTER MPA CONNECTION CIRCUIT
XR25 aid:*16 = XX.CO=> CO or CC- line 28 or 29 of the computer
*16 = XX.CC=> CC+ line 28 or 29 of the computer
16
XX = 14 => Cylinder 1 or 4 line 28 of the computer
XX = 23 =
> Cylinder 2 or 3 line 29 of the computerNOTES
Check the resistance of the coil.
Replace the coil if necessary.
Check the + after ignition feed to the coil concerned on track 3.
Repair if necessary.
The fault persists! Replace the injection computer.
IMPORTANT: The computer has probably been damaged by an electric shock. The cause of the damage
must be found before fitting a new computer.
Check the hygiene of the anti-interference condenser on track 4 of the coil.
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JSA052.0
INJECTION
Fault finding - Status and parameter checks
17
D7F 710
engine -
55 tracks
Engine stopped, ignition on.NOTES
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
1Dialogue
with XR25D13
(selector
on S8)Fault test
9.NJ
Use fiche 27
Code present
Deal with
fault
bargraph
2Change to
status testG01*
10.NJ
Status testNone
3Battery
voltage# 0411.8 < X < 13.2 V
DIAG 1
4Computer
configurationComputer configured to
manual gearbox
Computer configured to
automatic transmissionSee Fiche
’Reminder C’
to configure
the vehicle
5Immobiliser
(if option)Ignition onThis status bargraph must
be extinguished when
the ignition is on to
indicate that the
immobiliser is not active.
DIAG 12
1
19
19
1
1
3
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JSA052.0
INJECTION
Fault finding - Status and parameter checks
17
D7F 710
engine -
55 tracks
Engine stopped, ignition on.NOTES
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
6Throttle
position
potentiometer
.No load
# 17
Accelerator
pedal
slightly
depressed
Full load
# 1710 < X < 50
185 < X < 245
DIAG 2
7Pressure sensor
# 01X = Atmospheric
pressureDIAG 9
8Coolant
temperature
sensor# 02X = Engine temperature
± 5 °CDIAG 3
9Air
temperature
sensor# 03X = Temperature under
bonnet ± 5 °CDIAG 4
10 Fan assemblyG17*The fan must operateDIAG 17
11 Fault warning
lightSwitch
ignition onThe fault warning light
must illuminate then
extinguishDIAG 19
2
2
2
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JSA052.0
INJECTION
Fault finding - Status and parameter checks
17
D7F 710
engine -
55 tracks
Carry out the actions below if the engine does not start.
Otherwise, refer to the following pages.NOTES
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
1Flywheel signal
sensorStarterIlluminated if TDC
information detected
DIAG 5
2Fuel pump
G10*Fuel pump should be
heard to operateDIAG 6
3 IgnitionConnect
Optima
StationStarting test, complete
guide on Optima StationUse Optima
5800 Station
4Fuel pressureConnect
pressure
gauge to
fuel inlet
and activate
starter
motorThe pressure gauge must
show 2.5 bars Fuel pressure,
see Workshop
Repair
Manual or
section
5Injection
commandStarterFuel must come out of
the injector
DIAG 11
6Engine
compressionConnect
Optima
StationComplete guide on
Optima StationUse Optima
5800 Station
7 FlywheelConnect
Optima
StationOscilloscope.
Complete guide on
Optima StationUse Optima
5800 Station
3
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JSA052.0
INJECTION
Fault finding - Status and parameter checks
17
D7F 710
engine -
55 tracks
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
1Charging
circuit# 0413 < X < 14.5 V
DIAG 1
2Throttle
potentiometerNo loadIlluminated(does not
flash!)DIAG 2
3Idle speed
regulation# 06
# 12
# 21690 < X < 790 rpm
4 % < X < 14 %
- 4.3 % < X < 3.9 %DIAG 7
4Anti-pinking
circuit# 13 (at
3500 rpm,
no load)X variable and not zeroDIAG 8
5 Pressure circuit# 01
# 16270 ≤ X ≤ 430 V
X = atmospheric pressureDIAG 9
6Richness
regulation# 35
# 050 < X < 255
X varies around 128
50 ≤ X ≤ 900 V
DIAG 10
See also DIAG
15
7 Fuel pressureConnect a
pressure
gauge to the
fuel gallery
and activate
the starter
motorPressure gauge must
show
2.5 bars Fuel pressure,
see Workshop
Repair
Manual or
section
Carry out the actions below (engine warm, at idle speed, no consumers)
if the engine starts.
Otherwise refer to the previous pages.
NOTES
6
6
2
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INJECTION
Fault finding - Status and parameter checks
17
D7F 710
engine -
55 tracks
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
8Air
conditioningAC selected
# 06
# 44
# 06
# 44Extinguished if fast idle is
not active
Illuminated if the air
conditioning requests
compressor operation
Illuminated if the
injection authorises
compressor operation
690 ≤ X ≤ 790 rpm
300 ≤ X ≤ 4000 W
800 ≤ X ≤ 900 rpm
300 ≤ X ≤ 4000 W
DIAG 16
9Power assisted
steering
prestostatTurn wheels
to full lockIlluminated when wheels
turned to full lockDIAG 18
Carry out the actions below (engine warm, at idle speed, no consumers)
if the engine starts.
Otherwise refer to the previous pages.
NOTES
10
10
9
13
10
9
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Fault finding - Status and parameter checks
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D7F 710
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Check during road test.NOTES
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
1Vehicle speed
information# 18X = speed read on the
speedometer in km/h
DIAG 13
2Adaptive
richnessProgramm-
ing
# 30
# 31106 ≤ X ≤ 150
106 ≤ X ≤ 150 DIAG 14
3Emission of
pollutants2500rpm
after driving
At idle
speed, wait
for
stabilisationCO < 0.3 %
CO2 > 13.5 %
O2 < 0.8 %
HC < 100 ppm
0.97 < λ < 1.03
CO < 0.5 %
HC < 100 ppm
0.97 < λ < 1.03
DIAG 15
see also
DIAG 10
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JSA052.0
INJECTION
Fault finding - Status and parameter interpretation17
D7F 710
engine -
55 tracks
AFTER REPAIRStart the status and parameter check again from the beginning.
DIAG 1BATTERY VOLTAGEFiche n° 27
XR25 aid: Battery voltage ignition on, Minimum< # 04 < Maximum
Battery voltage idle speed, Minimum< # 04 < Maximum
No fault bargraphs should be illuminated.
No consumersNOTES
If # 04 < Minimum, the battery is discharged:
Check the charging circuit to determine the cause of this fault.
Ignition on
If # 04 > Maximum, the battery may be overcharged:
Check the charging voltage is correct with and without consumers.
If # 04 < Minimum, the charging voltage is too low:
Check the charging circuit to determine the cause of this fault.
At idle speed
If # 04 > Maximum, the charging voltage is too high:
The alternator regulator is faulty. Repair this fault and check the electrolyte level in the battery.
NOTE:
The battery and the charging circuit may be checked using the OPTIMA 5800 station (measurement does
not require the battery to be disconnected, which retains the memories of the computers).
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